JP2019122204A - Protective tube - Google Patents

Abstract

To simplify installation operation to a submarine cable or the like in a protective tube.SOLUTION: A protective tube 1 is formed by disposing sides of recessed surfaces 31a of a pair of halved tubes 3 to face each other. The halved tubes 3 are provided with a bolt coupling part 6 extended outside a bonded surface 34 with the facing halved tubes 3. The bolt coupling parts 6 have: bolt fixing parts 7 (first fixing parts) provided for one side edge parts of the recessed surfaces 31a of the halved tubes 3; and nut fixing parts 8 (second fixing parts) provided at axial symmetrical positions of the bolt fixing parts 7 and the halved tubes 3 on the other side edge part of the recessed surfaces 31a of the halved tubes 3. The fixing parts 8 can rotate a bolt 4 in the state that a head 41 of the bolt 4 is hooked between a first bolt angle B1 at which the bolt 4 is almost parallel to an opposite direction of the halved tubes 3 and a second bolt angle B2 at which the bolt 4 is in the direction having a prescribed angle against the first bolt angle B1.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a protective tube for protecting a submarine cable or the like.

  Conventionally, a submarine cable or the like laid on the seabed has been used for transmission of communication signals from island to island, power transmission, and the like. Such submarine cables and the like should not be damaged when they come in contact with reefs under the influence of ocean currents or waves, or when they come in contact with the bottoms of ships coming in and out, or dredging from ships. , Are protected by a protective tube placed around their circumference.

  As a protective tube for protecting a submarine cable or the like, for example, there is known one in which a plurality of cylindrical tubes formed by arranging a pair of half pipes facing each other are connected along the submarine cable or the like. When attaching a protective tube of this type to a submarine cable etc., the operator goes into the sea, arranges two half tube bodies around the outer periphery of the submarine cable etc, and accommodates the submarine cable etc. in a cylindrical pipe. A bolt is inserted into a connecting hole provided on the side of both the half tube bodies, and this is tightened and fixed with a nut (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 61-112515

  However, as in the conventional protective tube, it is a heavy labor for the worker to perform the operation of tightening the two half tube bodies with bolts and nuts at the seabed affected by the ocean current and waves. In particular, in environments where the transparency of sea water such as mud and mud is low, the visibility in the sea may be almost limited due to poor visibility, and it is necessary to insert a bolt into the connection hole or It becomes difficult to fit and screw a nut on the bolt shaft.

  The present invention was made in order to solve the above-mentioned subject, and an object of the present invention is to provide a protective tube which can streamline attachment work of a protective tube to a submarine cable etc.

  In order to achieve the above object, the present invention is a protective tube in which concave sides of paired half tube bodies are disposed to face each other, wherein the half tube body is the one with the opposing half tube body. A bolt connection portion is provided extending to the outside of the joint surface, and the bolt connection portion includes a first fixing portion provided at one side edge of the concave surface of the half tube, and the half tube The other side edge of the concave surface has a first fixing portion and a second fixing portion provided at an axially symmetrical position of the half tube, and the first fixing portion is a head of a bolt Between a first bolt angle substantially parallel to the opposing direction of the half tube body and a second bolt angle in which the bolt has a predetermined angle with the first bolt angle. And the bolt is rotatable.

  In the protective tube, the pair of half tubes preferably have the same shape.

  In the protective tube, the second fixing portion has a notch portion which allows the shaft portion of the bolt to pass when the bolt is rotated from the second bolt angle to the first bolt angle, and the bolt is the first bolt Preferably, a nut screwed into the shank of the bolt is fixed when in the corner.

  In the above protective tube, the first fixing portion has a concave bolt receiving portion, and the bolt receiving portion abuts against the head of the bolt on its inner wall surface to restrict the rotation of the bolt. Is preferred.

  In the protective tube, preferably, the first fixing portion has a nut locking portion that locks a nut screwed to the shaft portion of the bolt at the second bolt angle.

  In the protective tube, it is preferable that the half tube has a positioning portion provided in the vicinity of a joint surface with the opposing half tube.

  According to the present invention, a bolt or the like is locked in advance to the half tube body, and after the operator arranges the half tube body supplied to the seabed oppositely, the nut is loosened and the bolt is used as the second bolt angle. The two half tube bodies can be easily connected by turning them to the first bolt angle and tightening the nut again. Therefore, the protective tube can be attached to the submarine cable or the like by a simple operation of rotating the bolt, and the working efficiency can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS The perspective view which shows the structure which separated the protection pipe which concerns on one Embodiment of this invention, and the half pipe body which comprises a protection pipe. (A) is a perspective view which mainly makes the plane of the said half tube body, (b) is a perspective view which mainly makes a bottom face. (A) Left side view of the above half tube, (b) is a front view, (c) is a plan view, (d) is a rear view, (e) is a right side view, (f) is a side sectional view, (G) is a bottom view. (A) is an enlarged plan view around a bolt connection portion of a half tube, (b) is a side view including a partially transparent cross section. (A) is a bolt fixing | fixed part and nut fixing | fixed part of the said bolt connection part, and the structure which shows a structure in which a volt | bolt exists in a 2nd bolt angle is a perspective view, (b) is a side view partially including a transparent section. (A) is a bolt fixing | fixed part and nut fixing | fixed part of the said bolt connection part, and is a perspective view which shows the structure which the volt | bolt rotated, (b) is a side view containing a partially transparent cross section. (A) is a bolt fixing | fixed part and nut fixing | fixed part of the said bolt connection part, It is a perspective view which shows the structure which has a volt | bolt in a 1st bolt angle, (b) is a side view containing a partially see-through section.

  A protective tube according to an embodiment of the present invention will be described with reference to FIGS. 1 to 7. As shown in FIG. 1, a plurality of protective tubes 1 of the present embodiment are connected in series along the outer periphery of a protected tube 2 such as a submarine cable or a submarine water pipe. The protective tube 1 is a circular tubular member in which the concave sides of the pair of half tubes 3 (3A, 3B) are disposed to face each other. The illustrated half tube bodies 3A, 3B have the same shape as each other, and they are fixed by the bolt 4 and the nut 5.

  The material of the protective tube 1 is not particularly limited as long as it has sufficient rigidity and durability to sufficiently protect the protected tube 2 for a predetermined period, and is made of resin or cast iron, for example. In addition, since the protective pipe made of cast iron is heavy, it is difficult to fix with a resin belt or the like, and it is general to fix with a connection bolt and a nut.

  As shown in FIGS. 2 (a) and 2 (b) and FIGS. 3 (a) to 3 (g), the half pipe 3 is a straight pipe portion 31 mainly constituting a housing space for housing the protected pipe 2; A large diameter connecting portion 32 formed at one end of the pipe portion 31 and a small diameter connecting portion 33 formed at the other end of the straight pipe portion 31 are provided. The straight pipe portion 31, the large diameter connection portion 32, and the small diameter connection portion 33 are integrally formed with each other.

  The straight pipe portion 31 has a concave surface 31a forming an inner side surface, a convex surface 31b forming an outer side surface, and a bonding surface 34 (see particularly FIG. 2B) with the opposing half tube body 3. Further, the straight pipe portion 31 has positioning portions 35 (positioning convex portions 35 a to 35 d) provided in the vicinity of the joint surface 34. In the present embodiment, the positioning convex portions 35 a to 35 d are claw members protruding from the convex surface 31 b close to the joint surface 34, and the tip of the claw member is a half tube facing the joint surface 34. It protrudes to the 3 side (refer to FIG. 3 (a) (e)). The two positioning convex portions 35a to 35d are formed on one edge side of the convex surface 31b (35a, 35b), and two (35c, 35d) on the other edge side of the convex surface 31b.

  The arrangement interval of the positioning protrusions 35a and 35b on one edge side is wider than the arrangement interval of the positioning protrusions 35c and 35d on the other edge side (see FIG. 3C). When the two half tube bodies 3 are disposed opposite to each other, the small diameter connecting portion 33 side portion of the positioning convex portion 35a abuts on the large diameter connecting portion 32 side portion of the positioning convex portion 35c, and the positioning convex portion 35b The large diameter connecting portion 32 side portion and the small diameter connecting portion 33 side portion of the positioning convex portion 35d abut each other to position both (see also the right protective pipe 1 in FIG. 1). That is, positioning convex parts 35a and 35b on one edge side sandwich the positioning convex parts 35c and 35d on the other edge side, so that the two half tube bodies 3 arranged opposite to each other are prevented from being displaced in the axial direction At the same time, the positioning projections 35a to 35d abut each other, so that the two half tube bodies 3 can be locked so as not to be separated easily. In addition, the positioning part 35 is not restricted to a convex-shaped structure like the positioning convex parts 35a-35d mentioned above, For example, one member formed convexly fits in the other member formed concavely It may be a configuration. In addition, the number of places is not limited to four as illustrated.

  The large diameter connection portion 32 is a substantially hemispherical member formed of a circular arc larger than the straight pipe portion 31, and the storage portion 32a for housing the small diameter connection portion 33 of the adjacent protection tube 1 and the straight portion of the adjacent protection tube 1 And an inner opening 32b through which the pipe 31 is inserted (see FIG. 2 (b)). The small diameter connection portion 33 is a substantially semi-pan lid-like member consisting of a circular arc larger than the straight pipe portion 31 and smaller than the large diameter connection portion 32, and has a half disk-like opening outer collar 33a, an opening outer collar 33a, And a dome-shaped member 33 b connecting the straight pipe portion 31. Since the inner surface of the housing portion 32a of the large diameter connection portion 32 is concave and the outer surface of the dome-like member 33b of the small diameter connection portion 33 is convex, these function as a joint function to bend the adjacent protective tubes 1 Can be connected.

  The half tube 3 is provided with a bolt connection portion 6 extended outside the joint surface 34 with the opposing half tube 3 (in particular, refer to FIGS. 2 (a) and 2 (b) and 3 (g)). . The bolt connection portion 6 is extended at a connection point between the straight pipe portion 31 and the large diameter connection portion 32. The bolt connection portion 6 is formed by a first fixing portion (hereinafter referred to as a bolt fixing portion 7) provided on one side edge of the concave surface 31 a of the half tube 3 and the other side of the concave surface 31 a of the half tube 3. And a second fixing portion (hereinafter, a nut fixing portion 8) provided at the edge. The bolt fixing portion 7 and the nut fixing portion 8 are provided at axially symmetrical positions of the half tube 3 with each other, and when the two half tubes 3 are disposed to face each other, the joint surfaces 34 of the two are in contact with each other. Contact.

  As shown in FIGS. 4A and 4B, the bolt fixing portion 7 includes a bolt accommodating portion 71 in which the head 41 of the bolt 4 (see also FIG. 5B described later) is accommodated; And a bolt shaft hole 72 for taking out the portion 42 to the outside of the bolt accommodating portion 71. The enlarged view in FIG. 4A shows an example in which the bolt 4 is inserted. The bolt 4 is preferably a hexagonal bolt whose head 41 is a hexagon, and the nut 5 is preferably a hexagonal nut whose shape is substantially the same as the head 41 of the bolt 4. The bolt fixing portion 7 is a member whose external appearance is a rectangular solid, and is formed so that the bolt accommodating portion 71 has a concave shape from the surface opposite to the joint surface 34. The distance D between two surfaces of the inner wall surface of the bolt housing 71 parallel to the axial direction of the half tube 3 is smaller than the maximum diameter (the length of the diagonal of the hexagon) of the head 41 of the bolt 4 It is slightly larger than the smallest diameter of the four heads 41 (the distance between the opposite sides of the hexagon). Therefore, the rotation of the bolt 4 inserted into the bolt housing 71 is restricted because the head 41 abuts against the inner wall surface of the bolt housing 71 and is sandwiched therebetween. The bolt 4 is not limited to the above-described hexagonal bolt, and may be, for example, a T-shaped bolt or the like in addition to a head portion 41 having a polygonal shape. The bolt 4 may be a square bolt (not shown) because the rotation restriction due to the contact with the inner wall surface of the bolt housing portion 71 and the hooking area with the rotation surface become large. However, a bolt with an octagon or more is not preferable because the contact area with the inner wall surface of the bolt housing 71 is reduced.

  The bolt shaft holes 72 are continuously opened from the bolt accommodation portion 71 in two axial directions in the direction of the joint surface 34 and in the direction orthogonal thereto. The width of the bolt shaft hole 72 is narrower than the width of the head 41 of the bolt 4. The peripheral edge (rotational surface 73) of the bolt shaft hole 72 on the bolt accommodation portion 71 side has a quarter arc shape in a side view (see FIG. 4B), and the bearing surface of the head 41 of the bolt 4 It will be installed. With this configuration, with the head 41 of the bolt 4 hooked on the pivoting surface 73, the bolt fixing portion 7 uses the arc-shaped center of the pivoting surface 73 as the pivoting axis P, and the bolt 4 is a half tube The bolt 4 is made rotatable between a first bolt angle B1 substantially parallel to the opposing direction of 3 and a second bolt angle B2 in which the bolt 4 is in a direction having a predetermined angle with the first bolt angle B1. . The second bolt angle B2 in the present embodiment is substantially orthogonal to the first bolt angle B1 and in a direction parallel to the axial direction of the half tube 3. The second bolt angle B2 is a bolt 4 (a nut screwed to the body portion 42) mounted on the bolt fixing portion 7 of one of the two half tube bodies 3 when the two half tube bodies 3 are disposed opposite to each other. 5) may be at an angle that does not make contact with the nut fixing portion 8 of the other half tube 3. Therefore, the second bolt angle B2 is not limited to the case where it is approximately 90 ° with respect to the first bolt angle B1 as illustrated, but may be an angle of 90 ° or less or 90 ° or more. However, when the second bolt angle B2 is 90 ° or less, there is a possibility that the bolt 4 may be partially protruded in the opposite direction from the joint surface 34. In addition, when the second bolt angle B2 is 90 ° or more, the range in which the bolt 4 is rotated is increased, which may lower the working efficiency. Therefore, the second bolt angle B2 is preferably in the range of approximately 90 ° ± 10 ° with respect to the first bolt angle B1.

  Further, the bolt fixing portion 7 has a nut locking portion 74 that locks the nut 5 screwed to the body portion 42 of the bolt 4 at the second bolt angle B2. The nut locking portion 74 is formed in a concave shape so that the nut 5 (the washer 51) is fitted around the periphery of the portion where the bolt shaft hole 72 is opened in the surface direction orthogonal to the joint surface 34.

  The nut fixing portion 8 communicates with the notch portion 81 which allows the body portion 42 of the bolt 4 to pass when the bolt 4 rotates from the second bolt angle B2 to the first bolt angle B1, and communicates with the notch portion 81. And the bolt shaft groove 82 in which the body portion 42 of the bolt 4 is accommodated when the first bolt angle B1. The notch portion 81 of the nut fixing portion 8, the bolt shaft groove 82, and the bolt shaft hole 72 of the bolt fixing portion 7 communicate in the opposing direction when the two half tube bodies 3 are opposed to each other. Further, the nut fixing portion 8 has a nut fastening portion 83 to which a nut 5 (a washer 51) screwed to the body portion 42 of the bolt 4 is fastened and fixed at the periphery of the bolt shaft groove 82. The nut fastening portion 83 is formed in a shape into which the nut 5 (the washer 51) is fitted.

  The attachment procedure of the protective tube 1 configured as described above will be described with reference to FIGS. 5 (a) and 5 (b) to 7 (a) and 7 (b) in addition to FIG. 1 described above. The half pipe body 3 is transported on land or the sea in a state where the bolt 4 and the nut 5 are attached to the bolt fixing portion 7 in advance, and is handed over to a worker who performs work in the sea. As shown in FIGS. 5A and 5B, at this time, the bolt 4 is disposed at the second bolt angle B2, and the nut 5 is released so that the nut 5 is locked by the nut locking portion 74. It is screwed in the fastening direction rather than the position. Therefore, when the half tube body 3 is transported, it is possible to suppress the nut 5 from being detached from the bolt 4 without generating noise due to the swing movement of the bolt 4.

  The worker who receives the half tube 3 with the bolt 4 and the nut 5 connects the two half tubes 3 so that the concave surfaces 31a face each other, as shown in FIG. It arrange | positions on the outer periphery of the to-be-protected pipe 2 so that the small diameter connection part 33 of the protective pipe 1 which the part 32 adjoins may be covered. Since the pair of half pipes 3 constituting the protective pipe 1 have the same shape, the worker in the sea or a person who supplies the half pipe 3 to the worker from the sea can use either the upper pipe or the lower pipe. There is no need to make a distinction, and it is sufficient to sequentially assemble the half tube bodies 3 supplied to the seabed, and it is possible to improve the operation efficiency of attaching the protective tube 1. In addition, when the two half tube bodies 3 are arranged to face each other, the positioning convex portions 35a to 35d function, so that, for example, even in the sea with poor visibility and ocean current or waves, the worker is The half tube 3 can be easily positioned.

  Next, the operator loosens the nut 5, and as shown in FIGS. 6A and 6B, the bolt 4 changes from the second bolt angle B2 to the first bolt angle B1 with the pivot axis P as an axis. Make it rotate. The number of times of rotation of the nut 5 necessary for loosening the nut 5 is the length of the bolt shaft hole 72 in the second bolt angle direction, the depth of the nut locking portion 74, and the washer 51 (in the illustrated example, a spring washer Is also designed in consideration of the thickness etc.), but it is designed so that the locked state of the nut 5 can be released by the number of times less than 3 rotations, more preferably less than 2 rotations. preferable.

  Since the corner of the bolt fixing portion 7 adjacent to the bolt shaft hole 72 is chamfered, the bolt 4 can be smoothly rotated without the bearing surface of the nut 5 (washer 51) coming into contact with the corresponding portion. it can. In addition, the corner close to the notch 81 of the nut fixing portion 8 is also chamfered in the same manner as described above.

  As shown in FIGS. 7 (a) and 7 (b), the operator arranges the bolt 4 at the first bolt angle B1, and fastens and fixes the nut 5 to the nut fastening portion 83 using a predetermined tool such as a ratchet. Do. At this time, since the bolt 4 is restricted so as not to be sandwiched and rotated by the inner wall surface of the bolt housing portion 71, the nut 5 can be fastened and fixed to the bolt 4 only by rotating the nut 5. Normally, the operation of fastening a nut to a bolt requires both hands because it is fixed so that the bolt does not rotate with one hand and the nut screwed to the shaft of the bolt is rotated with the other hand. . On the other hand, in the present embodiment, since the nut 5 can be fastened only by rotating the nut 5, the operation can be performed with one hand.

  The nut fastening portion 83 is engraved deeper than the outer surface of the nut fixing portion 8, and the notch 81 is thinner than the width of the nut 5 (the washer 51). The peripheral edge 83 restricts the movement of the nut 5 and the bolt 4 does not rotate. The number of times of rotation of the nut 5 necessary for fastening and fixing the nut 5 is the length in the first bolt angular direction of the bolt shaft hole 72 of the bolt fixing portion 7 and the length of the bolt shaft groove 82 of the nut fixing portion 8 Although it is designed in consideration of the depth of the nut fastening portion 83, the thickness of the washer 51 (including the spring washer in the illustrated example), etc., the number is less than 7 rotations, more preferably less than 5 rotations. Preferably, the nut 5 is designed to be able to be fastened and fixed.

  By the above procedure, the bolt fixing portion 7 and the nut fixing portion 8 on one side are connected. The worker may connect the bolt fixing portion 7 and the nut fixing portion 8 on the other side in the same procedure as described above. Although the bolt fixing portion 7 and the nut fixing portion 8 (bolt connecting portion 6) may be provided in the vicinity of the small diameter connection portion 33, the large diameter connection portion 32 covers the outer periphery of the small diameter connection portion 33. If the two half tube bodies 3 are connected in the vicinity of the large diameter connection portion 32, the small diameter connection portion 33 side is not separated.

  As described above, in the protective tube 1 of the present embodiment, the bolt 4 and the nut 5 can be locked in advance to the half tube 3, and the worker is provided with the half tube supplied to the seabed. After arranging the 3 oppositely, loosen the nut 5 and rotate the bolt 4 by a predetermined angle (in this embodiment, approximately right angle), and tighten the nut 5 again to make the two half tube bodies 3 easy Can be linked to That is, since it is not necessary to insert a bolt into the connection hole or to fit a nut into the shaft of the bolt, the worker can also work with a hand-cuff almost. Further, as described above, since the bolt 4 does not rotate, the fastening of the nut 5 can be performed by one hand work, and the operator can work stably in the sea by supporting the half tube body 3 with the vacant one hand. It can be performed. Therefore, even in an environment where the transparency of sea water such as mud and mud is low, the protective pipe can be attached to a submarine cable or the like by a simple operation of turning the bolt 4 to fasten the nut 5 As a result, it is possible to reduce the labor burden on workers and to improve work efficiency.

  The present invention is not limited to the above embodiment, and various modifications are possible. In the above embodiment, the head 41 of the bolt 4 is housed in the bolt housing portion 71 of the bolt fixing portion 7 and the nut 5 is fastened to the nut fixing portion 8. Can be accommodated, and the head 41 of the bolt 4 can be fastened to the nut fixing portion 8, that is, the bolt and nut can be reversed. However, if the bolt and nut are arranged in reverse, for example, if the body 42 of the bolt 4 is too long, there is also a problem that the end of the bolt portion projecting from the nut 5 touches the inner wall of the bolt housing 71. On the other hand, according to the arrangement of the bolts and nuts as in the above embodiment, the length of the body portion 62 of the bolt 4 is not limited, so that there is an advantage that the versatility is high.

  For example, in the above embodiment, the first bolt angle B1 in which the bolt 4 is substantially parallel to the opposing direction of the half tube 3 and the second bolt angle B2 in which the bolt 4 is substantially orthogonal to the first bolt angle B1. The bolt 4 can be pivoted between the two, but the first bolt angle B1 and the second bolt angle B2 can also include cases in which they are inclined within a predetermined range. In the above embodiment, the second bolt angle B2 is in the direction parallel to the axial direction of the half tube 3, but in the direction orthogonal to the axial direction of the half tube 3, ie, the bolt 4 is half. It may rotate toward the outside of the tube 3. However, since it is necessary to fit the bolt fixing portion 7 and the nut fixing portion 8 (bolt connecting portion 6) within the maximum width dimension of the large diameter connecting portion 32, secure a predetermined length for rotating the bolt 4 Above, as shown in the said embodiment, it is preferable that 2nd volt | bolt angle B2 is a direction parallel to the axial direction of the half tubular body 3. FIG. Further, in the above embodiment, the tip end (the nut 5 side) of the bolt 4 disposed at the second bolt angle B2 is oriented toward the small diameter connection portion 33, but is disposed 180 ° rotated with it The front end 4 (nut 5 side) may be disposed to face the large diameter connecting portion 32 (not shown). In this case, the bolt connection portion 6 may be provided with a space for accommodating the tip end of the bolt 4 between the large diameter connection portion 32 and the bolt connection portion 6. Moreover, while a commercially available product whose length, diameter, and the like are compatible can be used for the bolt 4 and the nut 5, the half tube body 3 itself is an object of an independent commerce.

DESCRIPTION OF SYMBOLS 1 protection pipe 3 half pipe body 31a concave surface 34 joint surface 35 positioning part 35a positioning convex part 35b positioning convex part 35c positioning convex part 35d positioning convex part 4 bolt 4 nut locking part 5 nut 6 bolt connecting part 7 bolt fixing part First fixed part)
8 Nut fixing part (second fixing part)
81 Notched part B1 1st bolt angle B2 2nd bolt angle

Claims (6)

A protective tube in which concave sides of paired half tubes are disposed to face each other,
The half tube body includes a bolt connection portion extended to the outside of a joint surface with the opposing half tube body,
The bolt connection portion is a first fixing portion provided at one side edge portion of the concave surface of the half-split tube body and the other side edge portion of the concave surface of the half-split tube body, and the first fixing portion And a second fixed portion provided at an axially symmetrical position of the half tube body,
The first fixing portion has a first bolt angle substantially parallel to the opposing direction of the half tube body and a bolt having a predetermined angle with the first bolt angle in a state where the head of the bolt is hooked A protective pipe characterized in that the bolt can be pivoted between a second bolt angle that is oriented.   The protective tube according to claim 1, wherein the pair of half tubes have the same shape.   The second fixing portion has a notch that allows the shaft portion of the bolt to pass when the bolt rotates from the second bolt angle to the first bolt angle, and the bolt is at the first bolt angle The protective tube according to claim 1 or 2, wherein a nut screwed to the shaft portion of the shaft is fixed. The first fixing portion has a recessed bolt receiving portion, and
The protective tube according to any one of claims 1 to 3, wherein the bolt storage portion abuts on a head of the bolt on an inner wall surface thereof to restrict rotation of the bolt.   The said 1st fixing | fixed part has a nut latching | locking part which latches the nut screwed together by the axial part of the volt | bolt in the said 2nd bolt angle, The 1st aspect any one of Claim 1 thru | or 4 characterized by the above-mentioned. Protective tube as described in.   The protective tube according to any one of claims 1 to 5, wherein the half tube has a positioning portion provided in the vicinity of a joint surface with the opposing half tube. .